The star of the FX series also admits he was initially hesitant about the crossover concept as 'It's Always Sunny in Philadelphia ... with something funny to do. Charlie Kelly fit so naturally ...

When “Abbott Elementary” creator Quinta Brunson mentioned the idea of a crossover episode with “It’s ... was Charlie’s illiteracy, which has long been referenced in “Always Sunny ...

It’s always busy for the It’s Always Sunny in Philadelphia cast.

The It's Always Sunny in Philadelphia half of the Abbott Elementary crossover is set to premiere in June, Rob McElhenney ...

Essentially, "bird law" is a total non-sequitur played off for laughs to show how out-of-depth Charlie is in the real world. It’s a nice wink to "Always Sunny" fans watching the crossover.

The episode, which debuted on January 8, was a crossover with "It's Always Sunny in... Charlie Day, Kaitlin Olson, Danny DeVito, Sheryl Lee Ralph, and Lisa Ann Walter are pictured in "Abbott ...

Whether it's ... Always Sunny cast] showing up to Abbott, so you’re getting two sides of a story,” she explained. “pov: abbott elementary fans who liked the always sunny crossover and ...